2 * Copyright (c) 2013 Cisco Systems, Inc. and others. All rights reserved.
4 * This program and the accompanying materials are made available under the
5 * terms of the Eclipse Public License v1.0 which accompanies this distribution,
6 * and is available at http://www.eclipse.org/legal/epl-v10.html
9 package org.opendaylight.controller.netconf.nettyutil;
11 import com.google.common.base.Optional;
12 import com.google.common.base.Preconditions;
13 import io.netty.channel.Channel;
14 import io.netty.channel.ChannelFuture;
15 import io.netty.channel.ChannelHandler;
16 import io.netty.channel.ChannelHandlerContext;
17 import io.netty.channel.ChannelInboundHandlerAdapter;
18 import io.netty.handler.ssl.SslHandler;
19 import io.netty.util.Timeout;
20 import io.netty.util.Timer;
21 import io.netty.util.TimerTask;
22 import io.netty.util.concurrent.Future;
23 import io.netty.util.concurrent.GenericFutureListener;
24 import io.netty.util.concurrent.Promise;
25 import java.util.concurrent.TimeUnit;
26 import org.opendaylight.controller.netconf.api.NetconfDocumentedException;
27 import org.opendaylight.controller.netconf.api.NetconfMessage;
28 import org.opendaylight.controller.netconf.api.NetconfSessionListener;
29 import org.opendaylight.controller.netconf.api.NetconfSessionPreferences;
30 import org.opendaylight.controller.netconf.nettyutil.handler.FramingMechanismHandlerFactory;
31 import org.opendaylight.controller.netconf.nettyutil.handler.NetconfChunkAggregator;
32 import org.opendaylight.controller.netconf.nettyutil.handler.NetconfMessageToXMLEncoder;
33 import org.opendaylight.controller.netconf.nettyutil.handler.NetconfXMLToHelloMessageDecoder;
34 import org.opendaylight.controller.netconf.nettyutil.handler.NetconfXMLToMessageDecoder;
35 import org.opendaylight.controller.netconf.util.messages.FramingMechanism;
36 import org.opendaylight.controller.netconf.util.messages.NetconfHelloMessage;
37 import org.opendaylight.protocol.framework.AbstractSessionNegotiator;
38 import org.slf4j.Logger;
39 import org.slf4j.LoggerFactory;
40 import org.w3c.dom.Document;
41 import org.w3c.dom.NodeList;
43 public abstract class AbstractNetconfSessionNegotiator<P extends NetconfSessionPreferences, S extends AbstractNetconfSession<S, L>, L extends NetconfSessionListener<S>>
44 extends AbstractSessionNegotiator<NetconfHelloMessage, S> {
46 private static final Logger LOG = LoggerFactory.getLogger(AbstractNetconfSessionNegotiator.class);
48 public static final String NAME_OF_EXCEPTION_HANDLER = "lastExceptionHandler";
50 protected final P sessionPreferences;
52 private final L sessionListener;
53 private Timeout timeout;
56 * Possible states for Finite State Machine
58 protected enum State {
59 IDLE, OPEN_WAIT, FAILED, ESTABLISHED
62 private State state = State.IDLE;
63 private final Promise<S> promise;
64 private final Timer timer;
65 private final long connectionTimeoutMillis;
67 // TODO shrink constructor
68 protected AbstractNetconfSessionNegotiator(final P sessionPreferences, final Promise<S> promise, final Channel channel, final Timer timer,
69 final L sessionListener, final long connectionTimeoutMillis) {
70 super(promise, channel);
71 this.sessionPreferences = sessionPreferences;
72 this.promise = promise;
74 this.sessionListener = sessionListener;
75 this.connectionTimeoutMillis = connectionTimeoutMillis;
79 protected final void startNegotiation() {
80 final Optional<SslHandler> sslHandler = getSslHandler(channel);
81 if (sslHandler.isPresent()) {
82 Future<Channel> future = sslHandler.get().handshakeFuture();
83 future.addListener(new GenericFutureListener<Future<? super Channel>>() {
85 public void operationComplete(final Future<? super Channel> future) {
86 Preconditions.checkState(future.isSuccess(), "Ssl handshake was not successful");
87 LOG.debug("Ssl handshake complete");
96 private static Optional<SslHandler> getSslHandler(final Channel channel) {
97 final SslHandler sslHandler = channel.pipeline().get(SslHandler.class);
98 return sslHandler == null ? Optional.<SslHandler> absent() : Optional.of(sslHandler);
101 public P getSessionPreferences() {
102 return sessionPreferences;
105 private void start() {
106 final NetconfMessage helloMessage = this.sessionPreferences.getHelloMessage();
107 LOG.debug("Session negotiation started with hello message {} on channel {}", helloMessage, channel);
109 channel.pipeline().addLast(NAME_OF_EXCEPTION_HANDLER, new ExceptionHandlingInboundChannelHandler());
111 // FIXME, make sessionPreferences return HelloMessage, move NetconfHelloMessage to API
112 sendMessage((NetconfHelloMessage)helloMessage);
114 replaceHelloMessageOutboundHandler();
115 changeState(State.OPEN_WAIT);
117 timeout = this.timer.newTimeout(new TimerTask() {
119 public void run(final Timeout timeout) {
120 synchronized (this) {
121 if (state != State.ESTABLISHED) {
123 LOG.debug("Connection timeout after {}, session is in state {}", timeout, state);
125 // Do not fail negotiation if promise is done or canceled
126 // It would result in setting result of the promise second time and that throws exception
127 if (isPromiseFinished() == false) {
128 negotiationFailed(new IllegalStateException("Session was not established after " + timeout));
129 changeState(State.FAILED);
131 channel.closeFuture().addListener(new GenericFutureListener<ChannelFuture>() {
133 public void operationComplete(final ChannelFuture future) throws Exception {
134 if(future.isSuccess()) {
135 LOG.debug("Channel {} closed: success", future.channel());
137 LOG.warn("Channel {} closed: fail", future.channel());
142 } else if(channel.isOpen()) {
143 channel.pipeline().remove(NAME_OF_EXCEPTION_HANDLER);
148 private boolean isPromiseFinished() {
149 return promise.isDone() || promise.isCancelled();
152 }, connectionTimeoutMillis, TimeUnit.MILLISECONDS);
155 private void cancelTimeout() {
161 protected final S getSessionForHelloMessage(final NetconfHelloMessage netconfMessage) throws NetconfDocumentedException {
162 Preconditions.checkNotNull(netconfMessage, "netconfMessage");
164 final Document doc = netconfMessage.getDocument();
166 if (shouldUseChunkFraming(doc)) {
167 insertChunkFramingToPipeline();
170 changeState(State.ESTABLISHED);
171 return getSession(sessionListener, channel, netconfMessage);
175 * Insert chunk framing handlers into the pipeline
177 private void insertChunkFramingToPipeline() {
178 replaceChannelHandler(channel, AbstractChannelInitializer.NETCONF_MESSAGE_FRAME_ENCODER,
179 FramingMechanismHandlerFactory.createHandler(FramingMechanism.CHUNK));
180 replaceChannelHandler(channel, AbstractChannelInitializer.NETCONF_MESSAGE_AGGREGATOR,
181 new NetconfChunkAggregator());
184 private boolean shouldUseChunkFraming(final Document doc) {
185 return containsBase11Capability(doc)
186 && containsBase11Capability(sessionPreferences.getHelloMessage().getDocument());
190 * Remove special inbound handler for hello message. Insert regular netconf xml message (en|de)coders.
192 * Inbound hello message handler should be kept until negotiation is successful
193 * It caches any non-hello messages while negotiation is still in progress
195 protected final void replaceHelloMessageInboundHandler(final S session) {
196 ChannelHandler helloMessageHandler = replaceChannelHandler(channel, AbstractChannelInitializer.NETCONF_MESSAGE_DECODER, new NetconfXMLToMessageDecoder());
198 Preconditions.checkState(helloMessageHandler instanceof NetconfXMLToHelloMessageDecoder,
199 "Pipeline handlers misplaced on session: %s, pipeline: %s", session, channel.pipeline());
200 Iterable<NetconfMessage> netconfMessagesFromNegotiation =
201 ((NetconfXMLToHelloMessageDecoder) helloMessageHandler).getPostHelloNetconfMessages();
203 // Process messages received during negotiation
204 // The hello message handler does not have to be synchronized, since it is always call from the same thread by netty
205 // It means, we are now using the thread now
206 for (NetconfMessage message : netconfMessagesFromNegotiation) {
207 session.handleMessage(message);
212 * Remove special outbound handler for hello message. Insert regular netconf xml message (en|de)coders.
214 private void replaceHelloMessageOutboundHandler() {
215 replaceChannelHandler(channel, AbstractChannelInitializer.NETCONF_MESSAGE_ENCODER, new NetconfMessageToXMLEncoder());
218 private static ChannelHandler replaceChannelHandler(final Channel channel, final String handlerKey, final ChannelHandler decoder) {
219 return channel.pipeline().replace(handlerKey, handlerKey, decoder);
222 protected abstract S getSession(L sessionListener, Channel channel, NetconfHelloMessage message) throws NetconfDocumentedException;
224 private synchronized void changeState(final State newState) {
225 LOG.debug("Changing state from : {} to : {} for channel: {}", state, newState, channel);
226 Preconditions.checkState(isStateChangePermitted(state, newState), "Cannot change state from %s to %s for chanel %s", state,
228 this.state = newState;
231 private boolean containsBase11Capability(final Document doc) {
232 final NodeList nList = doc.getElementsByTagName("capability");
233 for (int i = 0; i < nList.getLength(); i++) {
234 if (nList.item(i).getTextContent().contains("base:1.1")) {
241 private static boolean isStateChangePermitted(final State state, final State newState) {
242 if (state == State.IDLE && newState == State.OPEN_WAIT) {
245 if (state == State.OPEN_WAIT && newState == State.ESTABLISHED) {
248 if (state == State.OPEN_WAIT && newState == State.FAILED) {
251 LOG.debug("Transition from {} to {} is not allowed", state, newState);
256 * Handler to catch exceptions in pipeline during negotiation
258 private final class ExceptionHandlingInboundChannelHandler extends ChannelInboundHandlerAdapter {
260 public void exceptionCaught(final ChannelHandlerContext ctx, final Throwable cause) {
261 LOG.warn("An exception occurred during negotiation with {}", channel.remoteAddress(), cause);
263 negotiationFailed(cause);
264 changeState(State.FAILED);